[inspector] Further improve performance of `console.timeStamp()`.

This CL removes most of the overhead of the `ConsoleHelper` from the
implementation of `console.timeStamp()` by defering work to until it's
actually needed.

Bug: 350443026
Change-Id: I26a2bd3f246b24eaad349e213b17baeeed23fa6b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/5724349


Auto-Submit: Benedikt Meurer <bmeurer@chromium.org>
Reviewed-by: Simon Zünd <szuend@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/main@{#95131}